How to read a system check

Introduction
Lately, your wii has been doing strange things. It isn't quite bricked, but you get blackscreens, core dumps, or maybe it's printing money. You want to know what is wrong and you know that you could use a system check (aka syscheck) to see what is the problem. You just don't know how to read a system check.

Spoiler

What a system check looks like
There are several programs which can make a system check, like dop-mii, syscheck and syscheckGX. We will only look at a system check made by syscheck. Anyway, let's see what a system check looks like!

How to read it and what to look forThe homebrew channel IOS
When we take a look at the system check, we see that the first thing it reports is which IOS is used to run the syscheck, which is IOS58 in this case. This is important information, because this is the same IOS the homebrew channel will use. So if you are having problems with homebrew apps, it is probably caused by this IOS.

The cIOS
The next thing to look for are the cIOS. The cIOS all have a number higher than 200. In this case, cIOS202, cIOS222, cIOS223, cIOS249, cIOS250 and cIOS254 are installed. Want you mainly want to look for, is that none of the IOS are a stub. Basically, a stub is a usless IOS which does nothing, installed by Nintendo. If they are stubbed, you will need to use a softmod guide to install the proper cIOS.
You should also make sure you have the recommended setup. The recommended setup here at wiihacks is (note, the system check will not report which base IOS the cIOS uses, only the version/rev):

Off course, you are free to decide your own setup, but this might be the cause of your problems.

cIOSCORP/DARKCORP
The last thing to look for is a cIOSCORP/DARKCORP installation. It can be recognized by checking the IOS with numbers lower than 200. If many of them have a rev number of 65535, it is quite certain that cIOSCORP/DARKCORP is present on the wii. If so, it is recommended that you uninstall it using the How to Uninstall cIOSCORP from your Wii Console guide. cIOSCORP/DARKCORP is only intended for advanced users, who know exactly how it works.

What to do if you don't understand this guide or are uncertain about your system check
Maybe, even after readin this guide, you still don't understand how to read a system check, or are just uncertain about your system check and want someone to take a look at it. No worries, just make a thread about the problem you are having and include the system check. Also take a look at: How to post a system check

That it folks!
I am sure this guide is far from finished and anyone who has a suggestion to improve this guide is requested to do so.